THE PREVALANCE OF ANTIBIOTIC-RESISTANT BACTERIA AND RELATED FACTORS IN INFECTED DIABETIC FOOT ULCERS TREATED WITH ANTIBIOTICS AT LOWER-LEVEL HOSPITALS

Abstract

Objectives: Antibiotic-resistant bacteria are an important concern in diabetic foot ulcer infections, especially in patients who have been prescribed antibiotics previously. The study aimed to determine the rate of antibiotic-resistant bacteria and their related factors in infected antibiotic-treated diabetic foot ulcers in lower-level hospitals to select appropriate antibiotics for treating foot infections.

Methods: A descriptive cross-sectional design was applied. The study included diabetic patients with foot infections who were treated with antibiotics in lower-level hospitals for at least 48 hours or more admitted to the Endocrinology Department of Cho Ray Hospital from November 2022 to May 2023. Infected foot ulcers were cultured for bacterial identification and an antibiogram was performed before using empirical antibiotics.

Results: The study included 99 patients with an average age of 60.0±11.0 years old, 65.7% male, average BMI of 20.2±3.7 kg/m2, average HbA1c of 10.0±2.4%, median duration of diabetes of 10 (3-15) years and median duration of lower-level hospital treatment of 8 (4-14) days. The percentage of bacteria in the culture samples was 71.7% (71/99) in which gram-negative bacteria accounted for 56.4% and gram-positive bacteria for 43.6%, of which methicillin-resistant Staphylococcus aureus (MRSA) accounted for the highest rate (28.2%), followed by Klebsiella pneumoniae for 14.1%. The rate of multidrug-resistant (MDR) gram-negative bacteria was 75.0% and that of MDR gram-positive bacteria was 76.5%. Factor associated with MDR Gram-positive bacteria was lower-level hospital stay more than 7 days (p=0.04).

Conclusions: Infected diabetic foot ulcers treated with antibiotics at the lower-level hospitals had a higher proportion of gram-negative bacteria than that of gram-positive bacteria, but MRSA had the highest rate of 28.2%. MDR gram-negative and gram-positive bacteria accounted for about 2/3 of patients. The factor related to MDR Gram-positive bacteria was lower-level hospital stay of more than 7 days.

Keywords: infected diabetic foot ulcer; antibiotic resistance; multi-drug resistant (MDR) bacteria